Hi Dave,
That is all very scary. The original garage was owned by Andy Mason, a good friend of mine for the years of business (!!) . He recommended the S- Type to me, as he launched the car as a leading memeber of the Jaguar team in the USA (LA - Cal) back in the day.
He assured me - when the light came on after three / four years of the cause and the importanct fact that it has no other effect on performance / fuel etc. In fact the figs i have quoted you are since the light.
However, given you advice I will now book the car into the "new" garage, for their thoughts and actions.
Thank you Dave, i shall keep you informed.
Kind regards
Dominic